Aeroplane-propeller.



1.1. MITCHELL. AEROPLANE PROPELLER.

APPLICATION FILED JAN. 4,1916- 1,185,524=. Patented May 30, 1916.

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JESSE J. MITCHELL) OF PARKIERSBURG, WEST VIRGINIA.

AEROPLANE-PROPELLER Specification of Letters Patent.

Patented May 30, 1916.

Application filed January 4, 1916. Serial No. 70,090.

To all whom it may concern aeroplane.

The object of the invention is to rovide an aeroplane propeller which is ad ustable vertically within an arc of a predetermined degree, in a ready and convenient manner,

to perform the described functions, andv which is applicable to any ordinary type of flying machine employing a tractor propeller.

The invention consists of the features of construction, combination and arrangement of parts herein fully described and claimed, reference being had to the accompanying drawings in which Figure 1 is a longitudinal section through a portion of the body of a flying machine showing the application of the invention. Fig. 2 is a side elevation of the ropeller and associated parts of the power p ant removed from the aeroplane body, and showing also the supports for the propeller frame. Fig. 3 is a top plan view of the parts shown in Fig. 2. section through the same. Fig. 5 IS a vertical transverse section on the line 5-5 of Fig. 3. Fig. 6 is a fragmentary perspective view of one of the bars of the fuselage and the trunnion bearing mounted thereon. Fig. 7 is a similar view of one of the bars of the triangular propeller carrying frame and the trunnion pin mounted thereon.

Referring to the drawings, 1 designates a. tractor propeller of conventional or other desired form which is mounted upon the forward end of a shaft '2 having a universal joint connection. as at 3, with the shaft -l of the driving motor 5, so as to permit the propeller and propeller shaft to be adjusted without interfering with the transmission of driving power to the propeller from the motor.

The propeller shaft 2 is journaled to rotate in bearings 6 upon cross bars 7 and 8,

Fig. 4 is a vertical longitudinal forming elements of a substantially triangular frame, which includes a pair of Iongitudinal side bars 9 extending forwardly in converging relationship. The bars 7 and 8 connect the bars 9 respectively at their for ward ends and at a point adjacent to and in advance of their rear ends, to produce spaced bearing supports which are rigidly tied or connected together and which are arranged ,in proper relationship to, maintain a proper workingalinement between the propeller and motor shafts.

The frame bars 9 are pivotally connected with supporting bars or members 10 of the nacelle or fuselage 10 of an aeroplane 11, and, as shown these pivotal connections are in the form of transverse trunnions 12 and 13 which are fitted in sockets 14 upon the rear ends of the bars 9 and keyed thereto by set screws or other suitable fastening means 15, the outer ends of said trunnions being journaled in bearings 16 upon the forward ends of the bars 10 between which the rear ends of the bars 9 are positioned. The trunnions are arranged in transverse alinement with a universal joint 3, thus adapting the propeller carrying frame to swing vertically with the propeller throughout a desired arc, say of 45, so that the propeller may be disposed for a working action for straightaway flight or for giving both a propelling and a lifting .action, which is desirable under many conditions. Such a propelling and lifting action, as an example, allows a greater load weight to be carried in a machine at a given capacity, and it also increases the climbing speed of the machine over machines with propelling plants which are arranged strictly for driving action in the direct line of flight.

It will be observed that the described construction of frame gives maximum supporting strength to sustain the strains resulting from the working thrusts of the propeller, while allowing ready and easy adjusting movements tolbe obtained. For the purpose of allowing these adjusting movements to In the present instance, I have shown the other trunnion 12 provided with a crank arm 19 coupled by a connecting rod 20 to a controlling level 21 in the cock pit or pilots compartment of the machine, which lever is provided with a spring actuated dog 22 for engagement with a rack 23 to lock the propeller in any position in its range of adjustand a lifting action of greater or less force dependent upon the angle of inclination of the propeller between thevertical and horizontal. Hence all of the available power of the propeller may be employed for straight flight or for a combined propelling and lifting action, so that whenever desired the pilot'may secure additional lifting power to enable a greater load weight to be carried or to increase the climbing speed of the machine.

I claim:

1. In a propelling mechanism for aeroplanes, the combination of a gliding structure, a motor mounted thereon and having a forwardly extending shaft, a propeller having a rearwardly extending shaft jointed to the forwardly extendin sh ft o the m tor,

a frame in which the propeller shaft is journaled,'said frame being pivotally supported upon the gliding structure at points in line with the pivotal coupling between said shafts, means for counterbalancing the weight of the frame and propeller, and means for vertically adjusting the swinging propeller frame.

2. In a propelling mechanism for aeroplanes, the combination of a gliding structure, a motor having a forwardly extending shaft, a tractor propeller having a rear- 7 wardly extending shaft jointed to the motor shaft, a swinging frame supporting said propeller, said frame comprising rearwardly diverging bars connected at their front ends and adjacent to their rear ends by cross bars provided with bearings for'the propeller shaft, bearings upon the gliding structure, trunnions carried by the divergent ends of the propeller frame and journaled in said bearings, a weighted counterbalancing arm connected with one of said trunnions, a

crank arm upon the other trunnion, adjusting mechanism connected with said crank arm, and means for locking said adjusting mechanism in adjusted position.

In testimony whereof. I afiix my signature in presence of two Witnesses,

JESSE J. MITCHELL. Witnesses:

JAMES BOOTH, CLARA B. OLIVER.- 

